Method of mining and handling coal



Sept. 8, 1953 E. RAMSAY Filed Feb. 5, 1951 ANDLING COAL 2 Sheets-Sheet 1 l l l i zi" TOR. A30/MWI HTTORA/Y Patented Sept. 8, 1953 PAT-:EN f@ EF-ICE :MET-Hop :F .MINI-NG ANDHANDLING GOAL Erskine Ramsay, firni'g'hain, ma.

Application February 5, 1951, Serial No. 209,389

lThisinvention -relates to na. method of mining coal and has -for fan object the provision of -a method which shall be efective-toebtain alarger percentage of-coal fromfagiven-area vthan has been theretofore-possible.

A further objectof the inventionis to :provide a method `of mining' coal which' vshall -be-effective to lren'iov'e-all coalffrom-a prescribed area without danger Ato workmen.

A still-further objectief'myinVentionis-tofpro- Vide an improved method ofniining 1coal ywhich shall include=improved means -forthecirculation of air through the working.

A still further object is--ftoprovide a moreeconomical method -of miningfthan-vhas heretofore been practiced and in which the -coal is mined and removed simultaneously.

`While my invention-is'particularly adapted for the mining of` coal employing-themining machine disclosed in my U. S. PatentNo.2,407,448fdated September l0, 1946, it will be apparent Lthat it may be practiced, using otherinachines.V Briefly, my invention is a-modiication of theretreating long wallmining method -and'includes as an initial operation, the drivingof'an'air Icourse which extends along two adjacent sides of the remote limit of the area to be -mined out. -This is 'followed by driving a'course parallel'toone-sideof the area remote from the -entry A'and drivingan intersecting course -on the-adjacent side, leaving a flank pillar'along the airco-urse-of a width approximating that of the first mentioned courses. Next a course is driven parallel tothe second course, leaving a .pillar between lit andthe second course. Then `by retreating-'down the third mentioned course, remove half 'the coal tin the pillar between it and the second course but leaving a sunicient'pillar to support-the secondcolirse and the main air course. Following this 'operation, successive parallel courses aredriven, leaving a pillar between each Vcourse and its next preceding course, The vcourses lare driven while advancing with the mining machine, and, A'while retreating along each course, the 'pillar between it and the next preceding r course :isre'l'nved entrely vand 'the vcoal is 'mined out "alongside the course. I n

As the ccal is removed, the overburden is Alallowed'tc m11 in which relieves 'the weight annie working face of the coal, thus requiring'a minimum of 'props and timberin'g if any, 'asthewo'rk proceeds. This method 'of 'opeiation provides two parallel "courses 'along the iside "o`f the area remote from the entry with va half width 'illar alongside the .proximate "course and a i'u'll 'width pillar between the bourses At the intersection between leach-course'and the main air course extending'atan angle thereto a short pillar is left if Vneeded to protect the main air course. Also, the gob when `andif made, is stacked, but notto the roof-inimost cases, alongside this-portion of the-airc'ourse thus-leaving enough space for airto pass. Airis suppliedto the working through-anair Aconduit from a suitable 'source of`supply 'as the workadvances vand Amay return by wayof the ret-urn air' courses. Whenthe area has been mined out except for the first two courses, the machine V4is-driven 'forwardly with spread cutter elements lalong the nearer course, removing-the half lpillarand half the full width pillar. Then by lretreating along 4theinore remote'cours'e with'relements spread apart-the area is' completelyy mined.

Anexample of my improved method is illustrated in the accompanying drawings, forming apart of'this: application, inwhich:

EFigs. land laare'diagrammaticplan views of a `coal 'mine in which my improved 'method of mining'is *being carried' out;

`Fig2 is adiagranimatic partial sectional View thereof; and,

Fig. v3 is a *diagranimatic partial 'plan view showin'g'alternative means forremoving the coal as itis mined` Referring vto 'the drawings, Ishow in Figs. 1 and 1a"a""section,or 'areao'f a coal mine the adjacent boundaries f which are indicated at A, B and C. The entry to the mine is indicated gener'allya-t D.

fMyiinproi/'ed r'e'th'od is fpreferably'ca'rried out, utilizing the nii-'ning machine illustrated, describedand claimed lirmny previously issuednPa'tent No. 2,407,443, :dated 'Septern'l'ler l0, 1946, though other mining -`r'na'chines may be employed to advantage. No detailed description of that machine is given herein. Two machines I4 and I4 .are shown diagrammatically in the drawing. Each isshown as embodying two cutter gangs I0 and H `pivotally 'mounted at I2 and I3 land extending forwardly of the machine. The cutter gangs AHl and I! may be `spread apart by means of lever arms I6 and Il as shown with machine Hi to thereby cut 'a relativ-ely widepath, or they `may kbe drawn close together as shown with machine M to cut 'a relatively narrow path one hal-f 'the width of that when spread apart. Each of the cutter gangs employs a plurality of cutter 'chains fl8 carrying cutter elements I9 which are 'so driven 'that the cutter elements o3 move rearwardly with the outer reach of each cutter chain.

In carrying out my improved method I iirst drive a combined air course and heading 2| along the boundaries B and C of the area to be mined. This combined course is driven with the cutter gangs l and Il close together so as to be of minimum width and so that the roof over the course will require little or no timber or other temporary support. This combined air course and heading extends along the boundaries B and C as shown in Fig. 1 until it reaches boundary l A. A second combined air course and heading 22 is next driven alongside the course 2| and parallel thereto leaving a ilanking pillar 23 therebetween which is of a width equal to that of the courses 2| and 22.

Following the driving of the course 22 a third course, indicated in dotted lines at 24 is driven alongside and parallel to the course 23, leaving a flanking pillar 25 between it and the course 22 equal in width to the course 22. The pillars between the courses are made of a width equal to the width of the courses so that when the machine is driven in a reverse direction as indicated by the arrow 2| on machine hi with the cutter` gangs spread, one half of the pillar on each side is mined out. When the course 24 is driven with the mining machine advancing and with the cutter gangs close together as indicated at 28, the course is driven until it reaches boundary A. As each course is driven to the boundary A, the cutters |0 and are spread apart and the niachine retreated to remove the pillars between the courses adjacent the boundary A and from a course 2| which is joined to and forms an extension of course 2|. The machine is then retreated With cutters drawn together a distance equal to the width of the pillar 23 to leave pillars 33 and 34. The cutters are then spread to remove coal on each side of the heading along paths 29 and 3B, each equal to one-half the width of the course or one-half the width of the adjacent pillar 26. This widens the heading to such an extent that the roof may fall in as indicated at 3|, thus relieving pressure on the adjacent face of the coal. Preferably, as the mining proceeds, the gob, or large stonesV are stacked between the pillars 33 and 34 as shown at 35, in such way as to permit the passage of air therethrough. In forming the course 2| and the pillars 33 it may be necessary to do some hand mining.

The operations just described are repeated until the prescribed area is mined out except for the flanking pillar 23 and one-half the flanking pillar 25. A machine may then move forwardly up the combined air course and heading 22 with cutters spread apart to remove the remainder of the flanking pillars 2E and one-half the pillar 23. It may return along the combined air course and heading 2| with cutter gangs spread apart to complete the removal of the flanking pillar 23 and to remove some coal along the boundary B of the area to be mined. When this has been accomplished, substantially all the coal in the prescribed area will have been removed.

During the mining operation, air under pressure from a blower (not shown) is carried to the mining machines through hose 31 to insure fresh air to the operators of the mining machines at all times. Air is forced into the workings through the air courses and through the headings being driven from whence it passes, as indicated by the arrows, through the gob into the combined 4 heading and air courses 2| and 22 from whence it returns to the entry, The pillars between passages may be cut at suitable intervals, as shown at 35 for the passage of air. Water may also be supplied to the working face of the coal, as is well understood. Preferably a brattice 3B is erected to separate the course 22 from the worked out area.

During the mining operations, the coal mined by each machine is continuously removed from the machine by means of a conveyor indicated diagrammatically at 4|. 'I'he convey-or may extend rearwardly over tracks 42 and 43 to deliver its coal selectively yinto mine cars indicated at -44 and 4B. The mine cars convey the coal out of the mine or heading in a manner well understood.

As an alternative, the conveyor 4I may be made to deliver its coal into a continuously operating conveyor 41 which conveys the coal out of the mine or heading. The details of such conveyors are not herein illustrated and described as they are well known in the art.

From the foregoing it will be apparent that I have devised an improved method of mining and handling coal which results in a continuous break-down of the over-burden thereby relieving weight on the pillars and on the working face of the coal and making the coal easier to remove. When the time comes to draw the last of the pillars, the over-burden breaks down all around them and the removal of the coal is made easy.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are specically set forth in the appended claims.

What I claim is:

1. The method of mining coal which comprises driving air courses and headings along the remote side of the area to be mined and of a width such that the overburden requires little or no support, driving a second course parallel to and adjacent the first mentioned course and a third course parallel to and adjacent the second mentioned course leaving intervening flank pillars between the courses of a width approximating that of the iirst mentioned course and extending the entire length thereof, then while retreating removing from said third course approximately one-half the pillar between it and said second course and a like amount of coal from the other side of said third course, thereafter while advancing driving parallel courses to the rst, second and third mentioned courses each of said last mentioned courses being of a width while advancing such that the overburden requires little or no support and leaving a pillar between successive courses of a width approximately onehalf that of the next adjacent course and extending the entire length thereof, and while retreating removing said pillar.

2. The method of mining coal which comprises driving a combined air course and heading to and along the remote side of the area to be mined and of a width such that the overburden requires little or no temporary support, driving a second course parallel to and adjacent the rst mentioned course and a third course parallel to and adjacent the second mentioned course leaving flank pillars between the courses of a width approximating that of the first mentioned course and extending the entire length thereof, then While retreating removing from said third course approximately one-half the pillar between it and said second course and a like amount of coal from the other side of said third course, thereafter driving successive courses parallel to the rst, second and third mentioned courses each of said last mentioned courses being of a width while advancing such that the overburden requires little or no timber or other support and leaving a pillar between successive courses of a width approximately one-half that of the next adjacent course and extending the entire length thereof, and while retreating removing said pillar.

3. The method defined in claim 2 in which a combined heading and air course is initially driven along two adjacent remote sides of the area to be mined and in which the successive courses intersect the said heading and air course on one side of the area and are parallel to the said course on the other side.

4. The method defined in claim 2 in which a combined heading and air course is initially driven along two adjacent remote sides of the area to be mined and in which the successive courses intersect the said heading and air course on one side of the area and are parallel to the said course on the other side and in which pillars are left at the points of intersection of said successive courses and said initial course and in which the gob if any is loosely stacked between said last mentioned pillars.

5. The method dened in claim 2 in which two parallel courses are provided along one remote side of the area to be mined with a full width pillar between the courses and a half width pillar alongside the nearer course and in which the mining of the area is completed by removing the half width pillar and half the full width pillar, and removing the remainder of the full width pillar.

ERSKINE RAMSAY.

References Cited in the file of this patent UNTED STATES PATENTS Number Name Date 1,632,800 Pearce June 21, 1927 2,155,415 Fletcher Apr. 25, 1939 2,283,212 Joy May 19, 1942 2,330,437 Lovely Sept. 28, 1943 2,358,687 Cassidy et al Sept. 19, 1944 2,407,448 Ramsay Sept. 10, 1946 OTHER REFERENCES Mining Engineers Handbook by R. Peele, second edition, published by J. Wiley and Sons, Inc., New York, 1927, pp. 861, 

